Board of Supervisors President David Chiu will send a letter to the Pharmaceutical Research and Manufacturers of America asking them to fund a prescription drug disposal program in San Francisco.

San Francisco city officials are threatening to revive legislation requiring that the pharmaceutical industry operate a drug disposal program if it does not cough up money to keep The City’s existing one going.

San Francisco is among a number of cities grappling with what to do with unwanted drugs and questioning who should carry the burden of the cost.

Board of Supervisors President David Chiu said Tuesday that he will send a letter to Pharmaceutical Research and Manufacturers of America, a trade group, asking for funding.

“If that funding is not provided, I think that we should reconsider legislation to require drug companies doing business in San Francisco to pay for and operate a disposal program,” Chiu said.

The legality of such legislation is being tested by Alameda County, which last year became the first municipality in the nation to pass a law requiring drug makers to fund and operate disposal programs. The drug industry filed a lawsuit Dec. 7 to strike it from the books. The case is pending in the U.S. District Court of Northern California.

The lawsuit argues that the law is unconstitutional because it seeks to regulate interstate commerce.

San Francisco had debated a similar law in 2010, but amid opposition from the drug industry an agreement was struck where Pharmaceutical Research and Manufacturers of America and Genentech would contribute $110,000 for The City to launch a pilot program. The program began in April and is hailed as highly successful, but will terminate in June if more funding is not found.

Discarded medicines are seen as a threat to the environment and could end up in landfills or waterways. If left around homes, they can lead to abuse and fatal overdoses.

Under The City’s pilot program, the unwanted drugs are dropped off at 13 independent participating pharmacies and 10 police stations. Since April, nearly 11,000 pounds of unwanted drugs have been collected.